Modern internal combustion engines are designed to achieve the objectives of low weight, low cost, and high efficiency. Often, these objectives compete with each other such that meeting one objective can result in the failure to meet another objective. For example, modern engine designers aim to achieve a high efficiency engine by increasing the peak cylinder pressure (PCP) capability on the engine. However, in view of the high forces generated by the high PCP that are placed on the components of the engine, stronger materials and/or greater mass of materials are required. In most cases, stronger materials also are heavier. Therefore, it is difficult for modern engines to be highly efficient, while also being lightweight. Additionally, lightweight materials, such as aluminum, tend to have relatively poor fatigue strength, which further limits its viability in high PCP engines.
In view of the above constraints, some engines utilize through-bolt schemes that maintain a block in compression. However, conventional through-bolt schemes are not conducive to accommodating other engine components vying for space as such through-bolts occupy a significant amount of space and/or require repositioning of existing components. For example, the positioning of conventional through-bolts significantly affects the space available for features associated with the lubrication system, such as the main rifle and main journal feed drillings. Additionally, if a structural overhead member, such as a cam carrier is used, the structural features of the cam carrier supporting the cam shafts of the engine should not be deflected by the tension of the through-bolts.